SRF2011 - List of Authors (Kako, E.)

Paper

Title

Page

Adaptive Lorentz Force Detuning Compensation in the ILC S1-G Cryomodule at KEK

254

W. Schappert, R.V. Pilipenko, Y.M. Pischalnikov
Fermilab, Batavia, USA
H. Hayano, E. Kako, S. Noguchi, N. Ohuchi, Y. Yamamoto
KEK, Ibaraki, Japan

The recent tests of the S1-Global cryomodule at KEK provided a unique opportunity to compare the performance of four different styles of 1.3 GHz SRF cavities and tuners under similar operating conditions. Results of adaptive LFD compensation at gradients of up to 35 MV/m for DESY/Saclay, FNAL/INFN and KEK cavity/tuner designs are compared.

Poster MOPO064 [1.506 MB]

TUPO007

Development of STF Input Couplers for ILC

364

M. Satoh, E. Kako, S. Noguchi, T. Shishido, K. Watanabe, Y. Yamamoto
KEK, Ibaraki, Japan

High power tests of the STF-Phase 1 cryomodule was carried out at KEK-STF (Superconducting RF Test facility) in 2008. Vacuum leaks at the cold ceramic window of STF-1 input couplers were found in the disassembly of the cryomodule after warm-up. It was considered that the vacuum leaks might be caused by the thermal cycles. Structures of brazing parts at a ceramic disk was investigated to reduce the thermal strain. The STF-2 input couplers with an improved brazing structure for S1-Global cryomodule was designed after the thermal cycle tests of the sample RF windows. The results of the thermal cycle tests of the sample RF windows and the high power performance of the improved STF-2 input couplers will be reported.

Poster TUPO007 [1.034 MB]

TUPO030

Status of the 9-Cell Superconducting Cavity R&D for ILC at Hitachi

439

T. Watanuki, T. Semba, M. Watanabe
Hitachi Ltd., Ibaraki-ken, Japan
H. Hayano, E. Kako, S. Noguchi, T. Saeki, T. Shishido, K. Watanabe, Y. Yamamoto
KEK, Ibaraki, Japan

Hitachi is developing 9-cell superconducting cavities for ILC project in collaboration with KEK. We focus on electron beam welding (EBW) and plastic forming techniques. In 2010, Hitachi’s first 9-cell cavity without HOM couplers was completed successfully. Surface treatments and performance test of the cavity were carried out at KEK and the accelerating gradient reached 35.2 MV/m. We have undertaken the next 9-cell cavity with HOM couplers since January 2011. We will report the fabrication procedure and test result of first cavity and the current status of the next cavity.

FRIOA06

Construction of cERL Cryomodules for Injector and Main Linac

956

K. Umemori, T. Furuya, E. Kako, S. Noguchi, H. Sakai, M. Satoh, T. Shishido, K. Watanabe, Y. Yamamoto
KEK, Ibaraki, Japan
E. Cenni
Sokendai, Ibaraki, Japan
M. Sawamura
JAEA, Ibaraki-ken, Japan
K. Shinoe
ISSP/SRL, Chiba, Japan

The Compact ERL (cERL) project is advanced in Japan. Its aim is to demonstrate the circulation of 100 mA electron beams with energy of 35-200 MeV. Superconducting cavities are key components for realizing ERL. At injector part, electron beams are accelerated up to 5-10 MeV by three 2-cell cavities. Prototype 2-cell cavities show excellent performance of about 40 MV/m. However, heating problem exists on HOM couplers. Improvement of cooling is essential for stable CW operation. Input coupler is another big issue. High power test stand was constructed using a 300 kW klystron. Prototype couplers could deliver from several tens to a hundred kW of RF power. At main linac part, HOM damped 9-cell cavities are applied. Two prototype cavities were manufactured. Initially their performance was limited by field emission. But it was overcome and they reached to more than 20 MV/m. A prototype input coupler is also fabricated for main linac. It successfully propagates 25 kW standing wave and also thermal cycle tests were passed. Prototype HOM absorbers are also fabricated and several tests were carried out. For both parts, cryomodules are under construction. They will be completed in 2012.

Slides FRIOA06 [6.489 MB]

THIOA01

Test Results of the International S1-Global Cryomodule

615

Y. Yamamoto, M. Akemoto, S. Fukuda, K. Hara, H. Hayano, N. Higashi, E. Kako, H. Katagiri, Y. Kojima, Y. Kondo, T. Matsumoto, H. Matsushita, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, N. Ohuchi, T. Saeki, M. Satoh, T. Shidara, T. Shishido, T. Takenaka, A. Terashima, N. Toge, K. Tsuchiya, K. Watanabe, S. Yamaguchi, A. Yamamoto, K. Yokoya, M. Yoshida
KEK, Ibaraki, Japan
C. Adolphsen, C.D. Nantista
SLAC, Menlo Park, California, USA
T.T. Arkan, S. Barbanotti, M.A. Battistoni, H. Carter, M.S. Champion, A. Hocker, R.D. Kephart, J.S. Kerby, D.V. Mitchell, T.J. Peterson, Y.M. Pischalnikov, M.C. Ross, W. Schappert, B.E. Smith
Fermilab, Batavia, USA
A. Bosotti, C. Pagani, R. Paparella, P. Pierini
INFN/LASA, Segrate (MI), Italy
K. Jensch, D. Kostin, L. Lilje, A. Matheisen, W.-D. Möller, P. Schilling, M. Schmökel, N.J. Walker, H. Weise
DESY, Hamburg, Germany

S1-Global collaborative project by joint efforts of INFN, DESY, FNAL, SLAC and KEK, finished successfully at KEK- STF on February in 2011, is a crucial project for ILC. For this project, 8 SRF cavities, 2 from DESY, 2 from FNAL and 4 from KEK, were installed into one cryomodule with the thermal shields and the cooling pipes of liquid helium and nitrogen, cooled down to 2K totally three times, and cold-tested by using the three different frequency tuning systems (Blade tuner from INFN/FNAL, Saclay tuner from DESY and Slide-Jack tuner from KEK) and two types of input couplers (TTF III from DESY and STF#2 from KEK). During the cold test with high power, cavity performance, LFD (Lorentz Force Detuning) compensation by Piezo actuator, simultaneous 7 SRF cavities operation, dynamic heating loss measurement including static loss and DRFS (Distributed RF Scheme) operation with LLRF (Low Level RF) feedback system, were established successfully. In this talk, the results of the S1-Global cryomodule test are reported, discussed and summarized.

Slides THIOA01 [11.254 MB]

Paper	Title	Page
MOPO064	Adaptive Lorentz Force Detuning Compensation in the ILC S1-G Cryomodule at KEK	254
	W. Schappert, R.V. Pilipenko, Y.M. Pischalnikov Fermilab, Batavia, USA H. Hayano, E. Kako, S. Noguchi, N. Ohuchi, Y. Yamamoto KEK, Ibaraki, Japan
	The recent tests of the S1-Global cryomodule at KEK provided a unique opportunity to compare the performance of four different styles of 1.3 GHz SRF cavities and tuners under similar operating conditions. Results of adaptive LFD compensation at gradients of up to 35 MV/m for DESY/Saclay, FNAL/INFN and KEK cavity/tuner designs are compared.
	Poster MOPO064 [1.506 MB]

TUPO007	Development of STF Input Couplers for ILC	364
	M. Satoh, E. Kako, S. Noguchi, T. Shishido, K. Watanabe, Y. Yamamoto KEK, Ibaraki, Japan
	High power tests of the STF-Phase 1 cryomodule was carried out at KEK-STF (Superconducting RF Test facility) in 2008. Vacuum leaks at the cold ceramic window of STF-1 input couplers were found in the disassembly of the cryomodule after warm-up. It was considered that the vacuum leaks might be caused by the thermal cycles. Structures of brazing parts at a ceramic disk was investigated to reduce the thermal strain. The STF-2 input couplers with an improved brazing structure for S1-Global cryomodule was designed after the thermal cycle tests of the sample RF windows. The results of the thermal cycle tests of the sample RF windows and the high power performance of the improved STF-2 input couplers will be reported.
	Poster TUPO007 [1.034 MB]

TUPO030	Status of the 9-Cell Superconducting Cavity R&D for ILC at Hitachi	439
	T. Watanuki, T. Semba, M. Watanabe Hitachi Ltd., Ibaraki-ken, Japan H. Hayano, E. Kako, S. Noguchi, T. Saeki, T. Shishido, K. Watanabe, Y. Yamamoto KEK, Ibaraki, Japan
	Hitachi is developing 9-cell superconducting cavities for ILC project in collaboration with KEK. We focus on electron beam welding (EBW) and plastic forming techniques. In 2010, Hitachi’s first 9-cell cavity without HOM couplers was completed successfully. Surface treatments and performance test of the cavity were carried out at KEK and the accelerating gradient reached 35.2 MV/m. We have undertaken the next 9-cell cavity with HOM couplers since January 2011. We will report the fabrication procedure and test result of first cavity and the current status of the next cavity.

FRIOA06	Construction of cERL Cryomodules for Injector and Main Linac	956
	K. Umemori, T. Furuya, E. Kako, S. Noguchi, H. Sakai, M. Satoh, T. Shishido, K. Watanabe, Y. Yamamoto KEK, Ibaraki, Japan E. Cenni Sokendai, Ibaraki, Japan M. Sawamura JAEA, Ibaraki-ken, Japan K. Shinoe ISSP/SRL, Chiba, Japan
	The Compact ERL (cERL) project is advanced in Japan. Its aim is to demonstrate the circulation of 100 mA electron beams with energy of 35-200 MeV. Superconducting cavities are key components for realizing ERL. At injector part, electron beams are accelerated up to 5-10 MeV by three 2-cell cavities. Prototype 2-cell cavities show excellent performance of about 40 MV/m. However, heating problem exists on HOM couplers. Improvement of cooling is essential for stable CW operation. Input coupler is another big issue. High power test stand was constructed using a 300 kW klystron. Prototype couplers could deliver from several tens to a hundred kW of RF power. At main linac part, HOM damped 9-cell cavities are applied. Two prototype cavities were manufactured. Initially their performance was limited by field emission. But it was overcome and they reached to more than 20 MV/m. A prototype input coupler is also fabricated for main linac. It successfully propagates 25 kW standing wave and also thermal cycle tests were passed. Prototype HOM absorbers are also fabricated and several tests were carried out. For both parts, cryomodules are under construction. They will be completed in 2012.
	Slides FRIOA06 [6.489 MB]

THIOA01	Test Results of the International S1-Global Cryomodule	615
	Y. Yamamoto, M. Akemoto, S. Fukuda, K. Hara, H. Hayano, N. Higashi, E. Kako, H. Katagiri, Y. Kojima, Y. Kondo, T. Matsumoto, H. Matsushita, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, N. Ohuchi, T. Saeki, M. Satoh, T. Shidara, T. Shishido, T. Takenaka, A. Terashima, N. Toge, K. Tsuchiya, K. Watanabe, S. Yamaguchi, A. Yamamoto, K. Yokoya, M. Yoshida KEK, Ibaraki, Japan C. Adolphsen, C.D. Nantista SLAC, Menlo Park, California, USA T.T. Arkan, S. Barbanotti, M.A. Battistoni, H. Carter, M.S. Champion, A. Hocker, R.D. Kephart, J.S. Kerby, D.V. Mitchell, T.J. Peterson, Y.M. Pischalnikov, M.C. Ross, W. Schappert, B.E. Smith Fermilab, Batavia, USA A. Bosotti, C. Pagani, R. Paparella, P. Pierini INFN/LASA, Segrate (MI), Italy K. Jensch, D. Kostin, L. Lilje, A. Matheisen, W.-D. Möller, P. Schilling, M. Schmökel, N.J. Walker, H. Weise DESY, Hamburg, Germany
	S1-Global collaborative project by joint efforts of INFN, DESY, FNAL, SLAC and KEK, finished successfully at KEK- STF on February in 2011, is a crucial project for ILC. For this project, 8 SRF cavities, 2 from DESY, 2 from FNAL and 4 from KEK, were installed into one cryomodule with the thermal shields and the cooling pipes of liquid helium and nitrogen, cooled down to 2K totally three times, and cold-tested by using the three different frequency tuning systems (Blade tuner from INFN/FNAL, Saclay tuner from DESY and Slide-Jack tuner from KEK) and two types of input couplers (TTF III from DESY and STF#2 from KEK). During the cold test with high power, cavity performance, LFD (Lorentz Force Detuning) compensation by Piezo actuator, simultaneous 7 SRF cavities operation, dynamic heating loss measurement including static loss and DRFS (Distributed RF Scheme) operation with LLRF (Low Level RF) feedback system, were established successfully. In this talk, the results of the S1-Global cryomodule test are reported, discussed and summarized.
	Slides THIOA01 [11.254 MB]